This article discusses the introduction of Midrash Hallel, a late and obscure commentary to most verses of the Hallel Psalms (Ps 113-118), a well known Jewish prayer. The introduction is made up of passages taken from early midrashim and includes some meaningful variants. The author aims to establish the great value of the Hallel which is the quintessence of the psaulter, indeed of the whole Scripture and a compression of the Jewish history: the past, the present and the days of the Messiah. It also contains implicitly mystical and kabbalistic elements which have already been emphasized by scholars in other places of the text.